The term "VSTOL aircraft" is used herein to refer to both vertical take-off and landing aircraft and short take-off and landing aircraft. It is known in the art of VSTOL aircraft to deflect thrust from the engines of the aircraft downwardly for take-off or landing. Typical methods for deflecting thrust from the engines include deflector blades, rotatable engine nozzles and rotating the entire power unit.
Typical VSTOL aircraft, particularly those capable of attaining high speeds, use a combustion engine which acts as a pressurized gas generator to generate pressurized gas for propelling the aircraft. A problem faced with VSTOL aircraft is that the temperature of the pressurized gas is quite high, typically in the range of 1,000.degree. F. and higher, and the pressure is also considerable. When the pressurized gas is directed downwardly, the high temperature and pressure tends to melt tarmac, erode concrete and even heat metal plates below the aircraft to unacceptably high temperatures. The result is that operation of VSTOL aircraft is restricted, and take-off or landing must often be performed with some forward movement to reduce the damage.